<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			a{
				/*border: solid 1px red;*/
				/*padding-top: 30px;*/
				/*margin: 30px;*/
				padding-top: 20px;
				padding-bottom: 20px;
				border-bottom: solid 1px red;
				position: absolute;
				left:50%;
			}
			p{
				border: solid 1px blue;
			}
		</style>
	</head>
	<body>
		
		<p> p标签 </p>
		<div style="position: relative;border: solid 1px red;height: 100px;">
		 	<a href="#">a标签</a>
		 </div>
	</body>
</html>
